Absorptive switches are attractive components for a system designer, as the input, and ideally output, reflection coefficient of the switch remains constant regardless of the state of the switch. This reduces the effects of the switch on system parameters such as frequency pulling of a signal source, or the inducement of other transient effects that can be problematic in very short interval time-based systems.
One drawback of absorptive switches is that a dummy, or additional load, has to be included in the circuitry to be presented to the input network to absorb any incident energy when the switch is selected to be in a non-transmit or isolated state. This dummy load takes up valuable circuit board space in an integrated circuit (IC) design that directly translates to increased circuit cost and reduced yield.
Thus, there is presently a need for an absorptive switch which does not utilize a dummy load.